1. Technical Field
The present invention relates to a system and method for controlling a fail safe of a transmission for a vehicle, and more particularly, to a system and method for controlling a fail safe of a transmission for a vehicle capable of performing a fail safe control based on a temperature of the transmission during a failure in a transmission control unit (TCU).
2. Description of the Related Art
A transmission for a vehicle, particularly, an automatic transmission includes a transmission control unit (TCU) configured to change a shift level based on a driving state and a load state of the vehicle and sense a state of the transmission in real time, to perform a control of the transmission. The transmission is configured to operate as an intermediate leg that connects power of the vehicle to a driving shaft. Therefore, when a shift is not appropriately performed or when a transfer of the power is suddenly blocked, the transmission is not under a control of a driver. Therefore, driveability of the vehicle may be threatened and safety of a passenger may also be threatened.
Accordingly, a related art has developed a method “that includes performing communication between a TCU that is configured to operate a transmission and an electronic shift lever; drive a motor to pull an override cable connected to a parking sprag engaged with a parking gear when the electronic shift lever determines that the TCU is in a fail state after the communication; again determining, by the electronic shift lever, whether the TCU is in the fail state after the override cable is pulled; determining, by the electronic shift lever, a vehicle speed in response to determining that the TCU is in the fail state; and allowing, by the electronic shift lever, a driver to recognize that the vehicle speed is greater than a predetermined speed. However, even in the related art as described above, when a failure occurs in the transmission control unit while the vehicle is being driven, such that a hydraulic pressure change does not occur, safety may not be secured.
The matters described as the related art have been provided merely for assisting in the understanding for the background of the present invention and should not be considered as corresponding to the related art known to those skilled in the art.